The UK is seeking to dampen the row which threatens to divide the IPCC, the global climate research group.

The IPCC (the Intergovernmental Panel on Climate Change) is the UN-sponsored body researching human influences on the climate.

The US is seeking to replace the IPCC's chairman, the respected scientist Dr Robert Watson.

So the UK is proposing that the IPCC sidesteps the problem by electing two co-chairs.

The Bush administration is backing an Indian scientist, Dr Rajendra Pachauri, who heads the Tata Energy Research Institute.

It says it wants to see the election of someone from the developing world.

But it has not hidden its dislike for Dr Watson's willingness to tell governments what he believes to be the unvarnished truth - that human activities are now contributing dangerously to climate change.

Bound by the facts

President Bush repudiated the international climate agreement, the Kyoto Protocol, which is the only political instrument so far to result from the IPCC's work.

Dr Robert Watson: Contested election

Last year, the oil company ExxonMobil, which contributed to Mr Bush's election campaign, forwarded a memo to the White House asking whether Dr Watson could be replaced as the US representative on the IPCC, though the company states it has no official position on the matter.

The result of the election for chairman will be announced on 20 April in the Swiss city of Geneva, where the IPCC is meeting.

Dr Watson, a US citizen born in the UK, said he was confident of continuing. He said it was the IPCC's responsibility to point out the facts, though it was up to governments to decide whether to adopt policies on global warming.

The UK has said it "warmly endorses" Dr Watson's nomination, but suggested the possibility of co-chairs to preserve the IPCC's "remarkable consensus".

A British official told BBC News Online: "Dr Watson has done an excellent job, and we would like him to continue.

"But consensus is important with the IPCC, and always has been, which is why we are promoting a co-chair."

Backing for the UK has come from the former German environment minister, Dr Klaus Toepfer, who now heads the United Nations Environment Programme (Unep).

He told BBC News Online: "We should try to stick to the wonderful consensus culture of the IPCC. It's the best basis for scientific co-operation.

Politics irrelevant

"The UK's idea is more than a compromise, and it would be unfair to Dr Pachauri, who's an honest scientist and a respected candidate, to see co-chairs as any sort of second best.

"Don't shoot the messenger"

"There must be no question of triumphalism, or any country claiming victory here. What matters is the science, not what any individual government wants."

The man responsible for Dr Watson's original nomination to the IPCC, Dr John Gibbons, says he should stay.

Dr Gibbons, who was President Clinton's assistant for science and technology from 1993 to 1998, wrote to ExxonMobil to protest at its attempts to have Dr Watson "dumped" from the IPCC.

Unchallenged expertise

He wrote: " I recommended Watson to the President for the position because of his excellent record as a scientist, his extensive knowledge of climate change issues, and his diplomatic skills.

"Let's not throw out the messenger because we don't like the news. We can have our own opinions but we cannot all have our own facts."

Dr Gibbons told BBC News Online: "I didn't know what Watson's politics were at all - I chose him because of his standing in the scientific community.